Implementation of high speed 24-bit vedic multiplier
Kanak Kujur, Mayuri Dave, Pradnya Patil, Sakthivel R.
School of Electronics Engineering (SENSE), VIT, Vellore -632014
(FFT) is widely used for DSP processes. Which
represents signal in frequency domain reducing
the computation time required to do a
computation vastly. But the FFT Algorithm
uses greater number of complex multiplications
to generate an output leading to complex circuit
and delay. To overcome this vedic
multiplication technique is implemented to
increase the speed and efficiency of
multiplication.
The [2] IEEE Floating-Point Arithmetic
Standard (IEEE754) found in 1985 for
Floating-Point calculation presented by IEEE.
which determines arithmetic formats and
techniques for binary and decimal floatingpoint number arithmetic’s in computers. This
standard indicates special case conditions and
their default taking handling. This [3] reduced
the problem of reliability and portability issues
introduced by conventional methods. Today is
the most widely recognized representation for
genuine numbers on PCs.
Vedic Mathematics [4] is a combination of
Techniques/Sutras to solve mathematical
arithmetic in simple and quicker manner. It
comprises of 16 Sutras (Formulae) and 13 subsutras (Sub Formulae). The [5] UrdhvaTiryakbhyam Sutras and Nikhilam Sutras give
least demanding method for mental
computation when performing multiplication.
Be that as it may, Urdhva-Tiryakbhyam utilizes
parallel multiplication and shows high
parallelism contrasted with other parallel
multipliers. UT [6] is the general technique
appropriate to all form of multiplication and
furthermore in the division of a huge number by
another huge number.
In this paper we are going to see usage of
24-bit floating point vedic multiplier dependent
on Urdhva-Tiryakbhyam Algorithm which is
called as vedic math Algorithm the architecture
and implementation of the multiplier is
elaborated further below and compared with
nominal multiplication method which also use
floating point representation.
Abstract: - In this age of technology, where
large amount of work is based on
computation of digital data the computation
capability and complexity of various data
processing devices and applications is vastly
reduced as signals are represented in
frequency domain with the help of FFT
technique. As large amount of application
use FFT processing technique for processing
data at high rate with efficiency the process
deals with multiplication which takes large
time for computation. To improve this an
ancient mathematic technique called Vedic
Multiplication technique is implemented.
The Vedic Multiplication technique from
Urdhva Tiryakbhyam Sutra which is one of
the ancient Indian mathematic method for
solving multiplication, showing a high
efficiency than conventional multiplication.
Here we have implemented IEEE754
Floating Point Representation to represent
the numbers. The vedic multiplication is
used to do multiplication of mantissa part
within this paper 24-bit floating point in
IEEE754 floating point representation
multiplication is implemented using vedic
multiplication. All the work is carried out on
Quartus Prime v18.1 a programmable logic
device design software and synthesis is done
using modelsim v10.5b software.
Keywords–Fast Fourier Transform (FFT),
(UT)
Urdhva-Tiryakbhyam,
Vedic
mathematics
INTRODUCTION
The rapid growth of the science and
technology lead to huge sum of invention and
discover and digital devices is one of them
becoming a large step toward automated device
and easing the daily work. These [1] devices
require to computation in digital format
consisting of arithmetic and logical process as
the technology advanced new techniques are
introduced from which Fast Fourier Transform
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ARCHITECTURE
input N digit multiplicand a and
multiplier b
1. Vedic Math’s: - It is a method based on
reasoning and mathematical working based on
old Indian teaching called Veda. To be
increasingly explicit, it has begun from
"Atharva Vedas" the fourth Veda. Which is
conceivable because of the endeavors of
Jagadguru Swami Bharathi Krishna Tirtha Ji of
Govardhan Peeth, Puri Jaganath (1884-1960).
Vedic Math's gives answer in one line where as
ordinary strategy requires a few stages. It is an
antiquated
system,
which
simplifies
multiplication, divisibility, complex numbers,
squaring, cubing, square and cube roots. In any
event, repeating decimals and auxiliary fraction
can be taken care of by Vedic Mathematic. The
Sutras Urdhava-Tiryakbhyam and Nikilam
Sutras shows most effortless method for mental
estimation when performing multiplication.
multiply a0 and b0
multiply a0 & b0 and multiply
a1 & b0 and store the result
multiply a1 and b1
2. UT Algorithm:- "Urdhva-Tiryakbhyam"
signifies "Vertically- crosswise" in Sanskrit.
Urdhva Tiryakbhyam (Urdhva Tiryak) is
Shortcut (General) Method of multiplication in
Vedic Mathematic for a wide range of numbers.
UT Sutra utilizes parallel multiplication and
shows high level of parallelism contrasted with
other parallel multipliers. In nominal parallel
multiplication technique fractional part get
summed after getting all partial product. On
account of UT, multiplication vertically and
transversely implies summation will occur soon
after partial products gets created.
final result is obtained by grouping
all the result
Fig 2: - Flow Chart
The above implementation shows how to
multiply ‘N’ large bit (N-bits x N-bits) by
𝑁
breaking it in smaller parts ( 2 = 𝑛 𝑒𝑎𝑐ℎ) and
this are further sub-divided into smaller part till
it reaches the smallest value i.e. 2-bit (2-bit x 2bit) hence simplifying the multiplication
process as shown in above picture.
3. IEEE 754 floating point standard: - It is
widely used today for DSP application.
IEEE754 floating point Standard is the widely
applied representation for non-complex
numbers on computers, including Intel PC’s,
Macs, and other platforms. Institute of
Electrical and Electronics Engineer [IEEE]
introduced a Standard for floating point
representation and arithmetic techniques. This
IEEE754
standard
is
the
generally
acknowledged representation for floating
numbers even though presence of many other
representations but IEEE 754 is the most
preferred one. The IEEE754 representation is
divided into three parts they are:
Fig 1: - Line Diagram/implementation of
UT Algorithm
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3. Add exponent bits; i.e. (E1 + E2 – Bias).
4. To generate the sign bits, apply XORing
to two sign bits; i.e. S1 ^ S2.
5. Normalize the result;
6. Truncate the results to fit in the available
bits of applied representation.
7. Check the underflow and overflow cases.
1. The Sign of Mantissa
2. The Biased exponent
3. The Normalized Mantissa
b) Vedic Multiplier implementation:
The proposed design implements vedic
mathematics based on Urdhva Tiryakabhyam
(UT) sutra for the multiplication of the mantissa
in IEEE754 single precision floating point
format. In this proposed multiplier the base
block used as first stage/base level
implementation is 3x3 block which is shown in
figure 6. Here we need 24bit vedic multiplier
for the multiplication of mantissa part. The
block diagram of 24-bit multiplier is shown in
figure 5.
Fig 3: - Pattern of Single Precision Floating
Point representation (IEEE-754)
METHODOLOGY
In this paper a Single precision(16-bit) floating
point multiplier is designed which overcomes
some basic problems. Below figure shows the
same.
The 3x3 block consists of three half adders,
three full adders as shown in figure 5. From 3x3
block, 6x6 multiplier block is designed. From
this 6x6 multiplier block, 12x12 multiplier
block is designed and similarly from this 12x12
multiplier block, 24x24 multiplier block is
designed and implemented using structural
approach in Verilog. These blocks require vedic
multipliers and carry look ahead adders (fast
adder) for getting the final output.
a) Floating point Multiplication Algorithm
Below figure shows the multiplication
format of two floating point binary digits in
IEEE 754 representation,
Fig 4: - IEEE-754 Floating Point multiplier
diagram [1]
Fig 5: - Main 24-Bit vedic multiplier block
diagram
The steps for floating point number (two no.)
multiplication is given below:
The above figure shows the main block and
below are the hieratical figure of internal block
showing the implementation of multiplier 3-bit
to the 24-bit
1. Multiply the two mantissas; i.e.(A*B).
2. Give a decimal point in the generated
result.
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Fig 6: - 3-Bit vedic multiplier block diagram
Fig 9: - 24-Bit vedic multiplier block
diagram
RESULT
The proposed 24-bit multiplier is implemented
in Verilog HDL and synthesized & simulated
using Quartus Modelsim simulator and verified
for possible inputs given below. Inputs are
generated using Verilog HDL test bench. The
simulation result for 24-bit vedic multiplier.
CASE - 1: Binary Value
Inputs a = 101010101010101010101010,
b = 110111011101110111011101
Product p = 10010011111010010011110101
1011000001011011000010
Fig 7: - 6-Bit vedic multiplier block diagram
Decimal value:
11184810 × 14540253 = 162629967156930
Here the RTL-Schematic, test bench waveform
is shown, which are generated using Modelsim
Fig 8: - 12-Bit vedic multiplier block
diagram
Fig 10: - 3-Bit vedic multiplier output
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References:
[1] A. M. M and R. R. J, “Implementation of
24 bit high speed floating point vedic
multiplier,” 2017 International Conference
on Networks & Advances in Computational
Technologies (NetACT), 2017.
[2] P. B. S. , S. S. Pai, S. B. , and S. S. Bhat,
“Design and Implementation of 8-Bit Vedic
Multiplier,” International
Journal
of
Advanced
Research
in
Electrical,
Electronics
and
Instrumentation
Engineering, vol. 02, no. 12, Dec. 2013
Fig 11: - 6-Bit vedic multiplier output
[3] A. Nanda and S. Behera, “Design and
Implementation of Urdhva- Tiryakbhyam
Based
Fast
8×8
Vedic
Binary
Multiplier,” International
Journal
of
Engineering Research & Technology
(IJERT), vol. 03, no. 03, Mar. 2014.
[4] A. D. Subudhi, K. C. Gauda, A. K. Pala,
and J. Das , “Design and Implementation of
High Speed 4x4 Vedic Multiplier
,” International Journal of Advanced
Research in Computer Science and
Software Engineering, vol. 04, no. 11, Nov.
2014.
[5] P. Mehta and D. Gawali, “Conventional
versus Vedic Mathematical Method for
Hardware
Implementation
of
a
Multiplier,” 2009 International Conference
on Advances in Computing, Control, and
Telecommunication Technologies, 2009.
Fig 12: - 24-Bit vedic multiplier output
Fig 13: - 24-Bit vedic multiplier output
CONCLUSION
A highly efficient method of vedic
multiplication, “Urdhva Tiryakbhyam Sutra”
based on Vedic mathematics is presented in this
paper. The code has been simulated on
Modelsim. The proposed Vedic multiplier is
faster than Nikilam Sutrams in terms of
execution time. The number of logic levels and
delay is being reduced using the UT sutra.
Vedic mathematics is a mental calculation
method that provides worldwide acceptance
because of its easiness and advantages.
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